Gas burner



W. A. AHERN GAS BURNER Filed Dec. 15, 1931 F f INVENTOR .9 2 WILLIAM A. AHERN BY E ATTORNEY 6 Patented Dec. 19, 1933 GAS BURNER, William A. Ahern, Worcester, Mass.

Application December 15, 1931 Serial No. 581,150

8 Claims. (Cl. 158-'-116) This invention relates to gas burners, and more particularly to a gas burner adapted for use in the fire boxes of domestic heating stoves, kitchen ranges, and the like. 7

Although many difierent forms of gasburners have been proposed in the past for heating and cooking purposes, these prior constructions have not in. general proven satisfactory. Some of them are capable of operation only at a. comparatively fixed fuel burning rate. Others are ineflicient. and wasteful of gas, or do not liberate the heat in the location where it can be utilized to the best advantage. Still others are com.- plicated and expensive to manufacture and install.

It is accordingly the main object of the present invention to overcome these difllculties, and to provide a simple and inexpensive gasburner which can be readily installed in stoves or go ranges, and which will produce complete combustion of the gas with the maximum liberation 01' heat.

It is a further object of the invention to provide a gas burner which can be operated satisj factorily at either high or lowfuel burning rates,

as desired.

It is a further object to provide a gas burner which can be altered readily to distribute the heat in the manner best adapted to the particular conditions encountered at installation.

with these and other objects in view, as will be apparent to those skilled in the art, my invention. resides in the combination ofparts set forth in the specification and coveredby the claims appended hereto.

Referring to the drawing illustrating one em bodiment of the invention, and in which like reference numerals indicate like parts,

Fig- 1 is a vertical section through a gas burner, the section being taken on the line 1--1 of Fig. 2;

Fig. 2 is a top plan view of the burner;

Fig. 3 is a view similar to Fig. 1, but with the burner altered to provide a different distribution of the flame; and

Fig. 4 is a view similar to Fig. 3, but with the burner altered to provide an increased fuel burning capacity.

The embodiment illustrated comprises a hollow base member 10' shaped to provide a. small central distributing chamber 11 and an outer annular chamber 12 concentric therewith. The central. chamber 11 is connected to the annular chamber 12 by means of four hollow radial arms 14,: which provide passages for: the flow. ofrgas and primary air. The member 10 may be supported in the fire box of a kitchen range or other stove in any suitable manner, and for this purpose I have shown an apertured lug 15 projecting horizontally from the outer wall of the annular chamber 12.

A boss 16 projects downwardly from the lower wall of the central chamber 11,, and this boss is provided with an internally threaded opening to receive the upper end of a vertical Venturi tube 18 which serves as a gas and air mixing device. Gas is introduced axially into the lower end of the tube l8.by meansof a gas inlet nozzle 19 to which a gas supply pipe 20 is connected. Primary air enters the lower end of the tube 18 through air inlet orifices 22 surrounding the gas nozzle 19. These air orifices 22 may be adjusted in size by means of a shutter 23, whereby the proportions of air and gas entering the mixing tube 18 may be controlled. It will be understood that the supply of gas may be varied by means of a suitable valve (not shown) in the pipe 20. The gas in entering the tube 18 produces an aspirating effect which draws into the tube the proper quantity of air through the openings 22, and the mixture of'air and gas flows upwardly to the central chamber 11 and. thence outwardly through the radial passages 14 to the annular chamber 12.

In order to provide a large gas burning capacity and an extensive incandescent surface for the transmission of radiant heat to the heat absorbing surfaces, such as the water back of a kitchen range, I have shown an outer cylindrical shell 25 and an inner cylindrical shell 26, mounted above and concentric with the annular chamber 12. These parts are so arranged that gas and air are discharged upwardly from the chamber 12 into the annular space 27 between the shells. In order that the mixture of gas'and air may escape from the space 2'7 and burn, I provide a large number of small openings or perforations 29 in the shell 25 and a large number of small openings or perforations 30 in the shell 26. The shells are of considerable height, preferably at least three or four inches, and the gas exit openings are located over substantially the entire area of the shells. An annular sealing cap ,31 is provided at the'top of the shells to prevent. the gas from escaping upwardly from the space 2'7 and to insure an adequate pressure within this space. The total area of the openings 29 and 30 is so proportioned to the quantity of gas tobe burned that in normal operation a sufllcierit pressure is always maintained in the annular space 27 to insure discharge of gas and air through all the openings. These openings are all effective for gas discharge, so that heat is produced low in the fire box where it may be readily absorbed by the water back. The shells 25 and 26, and the cap 31 are preferably comparatively thin and formed of a suitable heat resisting material, such as chrome steel, which can be maintained at a high temperature for the rapid radiation of heat.

It will be understood that when the burner is in operation, secondary air will flow upwardly around the outside of the shell to mingle with the ignited gas jets issuing from the openings 29, and additional secondary air ,will flow upwardly between the radial arms 14 to mingle with the ignited gas jets issuing from the openings 30. This secondary air serves to complete the combustion of the gas and provide an intense heat. I have found that the operation may be improved by providing a cylinder 33 to act as a battle and compel the secondary air to travel close to the burning gas. Thiscylinder 33 is somewhat smaller in diameter than the shell 26 and. is mounted concentric therewith. It is preferably formed of the same material as the shells, and itmay be supported by means of an annular flange 34 projecting upwardly from the upper wall of the central chamber 11. With this construction, the cylinder 33 and the inner shell 26 provide an annular passage which is open at the top. The base member 10 provides openings between the radial arms 14, and. these openings communicate with the annular passage so that secondary air may flow upwardly therethrough. I

When the supply of gas is reduced,'the velocity of the gas and air passing through the openings 29 and will decrease. As soon as this velocity becomes less than the rate of flame propagation in the mixture, there will be a tendency for the flame to strike back inside the burner and ignite the gas at the nozzle 19. In order to overcome this difiiculty and allow satisfactory operation at low fuel burning rates, I provide a flat annular plate 36 directly above the annular chamber 12. This plate 36 is provided with orifices 37 having a total area considerably less than the combined area of the openings 29 and 30. The velocity of flow through the. orifices 37 will exceedthe rate of flame propagation even when the burner is operating at a low capacity, and striking back of the flame will be prevented.

At certain times it may be desirable to concentrate the heat abovethe burners, and to reduce the quantity of heat radiated laterally therefrom.- This may be accomplished by replacing the outer shell 25 with an imperforate shell or cylinder 39,-as shown in Fig. 3. The parts 25 and 39 are made interchangeable, and the burner is so arranged that one part may be readily removed'and the other slipped on in its place. 'If desired, the sealing cap 31 may be re-. placed with a similar cap 40 having orifices-41 therein to provide upwardly directed jets of flame.

In case still further concentration of heat is desired above the burner, the imperforate cylindrical bafile 33 may be replaced by a cylinder 43 having a number of small openings or perforations 44 therein, as shown in Fig. 4. A circular cap 45 is provided to close the top of the cylinder 43, and this cap may have orifices 47 therein.

Gas and primary air enter the cylinder 43' through an opening 48 in the upperwall. of the central chamber 11. This opening may be closed by a plug 49, as shown in Fig. 1, when the bafile 33 is in use. The opening 48 is preferably considerably less in area than the total areas of the orifices 44 and 47, to prevent striking back of the flame.

The operation of the invention will now be clear from the above disclosure. Gas is supplied to the nozzle, 19 at a desired rate through the pipe 20, and primary air enters through the orifices 22 and is mixed with the gas in the Venturi tube 18. The mixture flows upwardly to the chamber 11, thence radially through the passages 14 to the annular chamber 12, upwardly through the orifices 37 to the space 27, and outwardly through the openings 29 and 30,

where it is ignited. The plate 36 prevents the The outer shell 25 provides an extensive incandescent surface which transmits heat by radiation directly to the water back of the range in which theburner .is installed. Since'primary air is mixed with the gas in the tube 18, the openings 29 are all effective as gas andair discharge orifices, and the burner provides heat well down in the fire box for the heating of water. If it is desired to dispense with the water heating at certain seasons of the year, or if there is no water back in the range, the burner can be easily changed to the arrangement shown in Fig. 3, which will give very little lateral radiation of heat. In case very high fuel burning capacities are desired, without heating the water back, the arrangement shown in Fig. 4 is desirable. It will thus be seen that I have provided a gas burner which is not only simply constructed and efficient, but also may be readily altered to meet varying conditions of use.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A gas burner comprising a base member shaped to provide an annular chamber, a pair of concentric cylindrical shells mounted above the chamber, the annular space between the shells communicating with the chamber, and the inner shell having openings therein for the escape of gas from the annular space, means to introduce gas into the annular chamber, and an annular cap mounted at the top of the shells so that a suflicient pressure may be maintained in the annular space to force the gas outwardly therefrom through the openings, the inner shell serving as the outer wall of a passage'which is open at the top and the base member being shaped to provide an opening communicating with said passage, whereby air may flow upwardly through the passage and past the issuing gas jets.

2. A gas burner comprising a base member shaped to provide an annular chamber, a pair of concentric thin perforated cylindrical shells mounted above the chamber with the annular space between the shells in direct. communication with the chamber, means to introduce gas into the annular chamber, and an annular cap mounted at the top of the shells so that a sufficient pressure maybe'maintained in the :an-

nular space to force the gas outwardly therefrom through the perforations in both the shells, the inner shell serving as the outer wall of a passage which is open at the top and the base member being shaped to provide an opening communicating with said passage, whereby air may flow upwardly through the passage and past the gas jets issuing from the perforations in the inner shell.

3. A gas burner comprising a base member shaped to provide an annular chamber, a pair of concentric thin cylindrical shells of considerable height mounted above the chamber with the annular space between the shells in direct communication with the chamber, both the shells being provided with small closely spaced openings throughout substantially their entire area, means to introduce a mixture of gas and primary air into the annular chamber, and an annular cap mounted at the top of the shells so that a suflicient pressure may be maintained in the annular space to force the gas and primary air outwardly therefrom through all the openings in both the shells, the inner shell serving as the outer wall of a passage which is open at the top and the base member being shaped to provide an opening communicating with said passage, whereby secondary air may flow upwardly through the passage to complete the combustion of the gas issuing into said passage.

4. A gas burner comprising a base member shaped to provide an annular chamber, a pair of concentric cylindrical shells mounted above the chamber with the annular space between the shells in direct communication with the chamber, the inner shell being perforated, means to introduce a mixture of gas and primary air into the annular chamber, and an annular cap mounted at the top of the shells so that a sufficient pressure may be maintained in the annular space to force the gas and primary air outwardly therefrom through the perforations in the inner shell, the inner shell serving as the outer wall of a passage which is open at the top and the base member being shaped to provide an opening communicating with said passage, whereby secondary air may flow upwardly through the passage to complete the combustion of the gas.

5. A gas burner comprising a base member shaped to provide an annular chamber, a pair of concentric cylindrical shells mounted above the chamber with the annular space between the shells in direct communication with the chamber, the inner shellbeing perforated, means to introduce a mixture of gas and primary air into the annular chamber, an annular cap mounted at the top of the shells so that a sufficient pressure may be maintained in the annular space to forcethe gas and primary air outwardly therefrom through the perforations in the inner shell, and a cylindrical bafiie concentrio with and smaller in diameter than the inner shell, the bafile and inner shell forming an annular passage which is open at the top and the base member being shaped to provide an opening communicating with said passage, whereby secondary air may flow upwardly through the passage to complete the combustion of the gas.

6. A gas burner comprising a base member shaped to provide a central distributing chamber, an outer annular chamber concentric therewith, and hollow radial arms providing passages leading from the distributing chamber to the annular chamber, a pair of concentric cylindrical shells mounted above the annular chamber with the annular space between the shells in direct communication therewith, the inner shell being perforated, means to introduce a mixture of gas and primary air into the distributing chamber and cause the mixture to flow through the radial passages and the annular chamber into the said annular space, and an annular cap mounted at the top of the shells so that a sufiicient pressure may be maintained in the annular space to force the gas and primary air outwardly therefrom through the perforations in the inner shell, the inner shell serving as the outer wall of a passage which is open at the top, and the parts being so constructed and arranged that secondary air may flow upwardly between the radial arms and thence into the said passage to complete the combustion of the gas.

7. A gas burner comprising a base member shaped to provide an annular chamber, a pair of concentric cylindrical shells mounted above the chamber with the annular space between the shells in direct communication with the chamber, the inner shell being perforated, a perforated annular plate located between the annular chamber and the said annular space, means to introduce a mixture of gas and primary air into the annular chamber, and an annular cap mounted at the top of the shells so that a suflicient pressure may be maintained in the annular space to force the gas and primary air outwardly therefrom through the perforations in the inner shell, the inner shell serving as the outer wall of a passage which is open at the top and the base member being shaped to provide an opening communicating with said passage, whereby secondary air may flow upwardly through the passage to complete the combustion of the gas, the perforated annular plate serving to bring about a localized increase in the velocity of the mixture of gas and primary air and thus prevent striking back of the flame.

8. A gas burner comprising a base member shaped to provide a central distributing chamber, an outer annular chamber concentric therewith, and hollow radial arms providing passages leading from the distributing chamber to the annular chamber, a pair of concentric cylindrical shells mounted above the annular chamber with the annular space between the shells in direct communication therewith, the inner shell being perforated, a perforated cylinder concentric with and smaller in diameter than the inner shell, the space within the cylinder communicating directly with the distributing chamber, means to introduce a mixture of gas and primary air into the distributing chamber, a circular cap mounted on top of the cylinder, and an annular cap mounted at the top of the shells, whereby a sufiicient pressure may be maintained in the space within the cylinder and the annular space between the shells to force gas outwardly therefrom through the perforations in the cylinder and the inner shell, the cylinder and inner shell forming an annular passage which is open at the top, and the parts being so constructed and arranged that secondary air may flow upwardly between the radial arms and thence into the said annular passage to complete the combustion of the gas.

WILLIAM A. AHERN. 

